Lectotypification of the Famennian pre-ovule Condrusia rumex Stockmans, 1948

Condrusia rumex Stockmans 1948 occurs in several localities of the Belgian Evieux Formation (late Famennian, Upper Devonian). It consists of a hastate organ borne at the tip of “slender, dichotomizing” axes. Various interpretations have been given to this intriguing structure, ranging from a spore-bearing organ to a fern prothallus but recent investigations consider Condrusia to be an ovulate structures produced by early seed plants. The genus Condrusia includes 3 species: C. rumex Stockmans, C. minor Stockmans and C. brevis Petrosjan. C. rumex was described by Stockmans in 1948, who provided a diagnosis and illustrations, but failed to designate a holotype. We are currently reinvestigating the genus and we here designate and illustrate a lectotype for the genus and species C. rumex.